Abstract:
:Spiral k-space magnetic resonance spectroscopic imaging (MRSI) requires high performance from gradient hardware systems. During the readout phase, oscillating gradients are continuously played out, which can cause undesired effects. These effects on the quality of SI data are non-intuitive because of their time-varying nature. In this work we describe the effects of undesirable gradient performance on SI. Measurements of the true readout trajectories were performed and the results were then used in the reconstruction process. The effects of these imperfections resulted in a spatially and spectrally varying amplitude and frequency modulation. The use of the measured trajectories in the reconstruction process yielded an up to 20% increase in signal amplitude recovery.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Kim DH,Spielman DMdoi
10.1002/mrm.20928subject
Has Abstractpub_date
2006-07-01 00:00:00pages
198-203issue
1eissn
0740-3194issn
1522-2594journal_volume
56pub_type
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